Pulley-block.



J. S. HALL.

PULLEY BLOCK.

APPLICATION FILED DEC. 7. 1914.

1 161295, Patented Jan. 4, 1916.

JOHN SMITH HALL, OF MONTIGELIIO, IOWA.

PULLEY-BLOCK.

Specification of Letters Patent.

1,16? ,295. v Patented Jan. 41;, 19116. Continuation of applicationSerial No. 835,806, filed may 2, 1914. This application filed Decemberif, 1914.

' Serial No. 875,852.

To all whom itcmay concern:

Be it known that I, JOHN SMITH HALL, a citizen of the United States, anda resident of Monticello, in the county of Jones and State of Iowa, haveinventeda new and useful'Pulley-Block, of which the following is aspecification.

My invention relates to pulleys of the self-locking type, in which arope, cord or chain is automatically caught and firmly held, and whichmay be instantly released by a slight movement of the slack end of therope either toward or from the pulleyblock.

This application is filed in lieu and in continuation of my applicationSerial Number 835,806, filed May 2, 1914, which I have abandoned,without, of course, aban doning the invention described and claimedtherein and which is hereby and herein reserved and covered.

The principal object of the invention is to provide co-acting lockingmeans which will effectively grip or .bind ropes or cords, or evenchains, Without the inclusion of adjustable elements, which latter havebeen found objectionable, because they are relatively expensive ofconstruction, Weak, prone to disorder and disarrangement, frequentlyinoperative, and further because it is often diflicult for a novice toeffect the proper adjustment. In this connection it may be said tobeanother object to attain the lockin result in a more facile, economicaland e cient manner than heretofore.

A still further object, and withal a principal one, is to provide anovel non-adjustable locking-shoe which by reason of its peculiarcoaction with the locking-dog adapts itself to various conditions, suchas larger, smaller, or worn ropes or cords, and even to chains.

A still further object is to provide a novel locking-dog .or lever whichis unitary or integral, which does not require assembling, and which isof unique construction.

Another object of the invention is to provide a durable, simple andreliable device, which is economic of construction, for accomplishingthe purpose set forth.

Concisely stated, the main object of the invention is to generallysimplify and improve the construction of devices of this Consideringsaid drawings in detail, and

referring to each element thereof by a distinguishing numeral, 11designates a shell or contaimng portion composed of two side platespreferably of identical shape and of any desired material, conforming ina general way to the shape of the parts when attached thereto and havingat its upper and lower ends perforations purposed to receive rivets,pins or bolts, 2 and 3 respectively,

these being adapted to join the two plates and hold them in spacedrelation to each other. On the rivet 2 may be secured a sing or hook forsuspending the block.

A grooved pulley 4 is rotatively attached to the shell by means of arivet 5 or the like,

and over said pulley the usual hoisting rope 6 is carried and its looseor slack end is passed between the lock-shoe 7 and the dog 8 andthreaded through the eye 9 on the lower end of said dog.

The loop-like skeleton shoe 7 secured 0pposite the serrated face of thedog is curvilinear-oblong or elliptical in outline and is pror'ided witha selectively straight or con cave erably constructed as shown in Fig.1, Where it is shown as secured within said shell by rivets 10 and 11,both of which it embraces. The shoe 7 is merely dropped into place oversaid rivets and is therefore not rigidly, but loosely held thereon, itbeing movable relatively thereto and therefore adjustable without theprovision of additional means for adjusting it or for holding it inadjusted position. Said shoe is preferably formed of a thin strip ofslightly resilient metal folded upon itself to loop over said rivetsand. its ends overlapped, as shown in Fig. 1. This construction providesfor the smooth or serrated face, but is pref-v easy renewal of. thelock-shoe should it become badly worn, through long usage, or should itbe broken.

The locking-dog 8, designed to engage the hoisting rope and force itagainst the shoe 7 is ogee or substantially S-shaped and has a convex oreccentrically formed and serrated face disposed opposite said shoe, andhas an integral eye or rin 9 horizontally positioned at its lower enSaid dog is pivotally mounted between the two plates forming the shellby means of a rivet or the like, 12, which rivet passes through asuitable aperture provided at the upper end of the do and through bothof said plates. This p acement of the dog relative to the shoe is suchthat when a rope, cord, or chain is interposed between their proximalfaces and threaded through the eye 9, reaching thence down to the handof the operator, a slight movement of the hand to pull said cord'outwardor inward respectively engages or disengages the cord. It will beevident that the concaved contact portion of the thin metallic stripcomprising the shoe 7 will yield if sufficient pressure be brought tobear thereagainst, but that nevertheless it will resist such pressure.Thus it will accommodate itself for cooperation with the dog 8 in orderto securely grip or bind cords or chains differing materially in theirsizes. It will be further evident that no adjustment of said shoe isrequired in order to effect that result; that the shoe and the dog aremade each of a single piece of metal and that it is thereforepractically impossible for either to become disordered or inoperative;that it can be operated by a novice; that the device is more economic ofmanufacture than those which have preceded it, and that it is moreefficient in operation than prior devices of similar character.

Another feature to be particularly noted is that the convex portion ofthe dog 8 will force the cord 6 into the concave face of the shoe 7.-Owing to the corresponding curvatures of the coacting binding portionsthe friction will be greater than if the cor responding face of the shoewere straight or plane, and much greater than if it were opposite incurvature, and that the cord will be looked much more securely than if ashoe having either of the latter character of faces is used.

In Fig. 3 I have illustrated a modified shoe, 7, which is in outline acontinuous loop having one serrated and one straight or plane face, thisshoe being reversible.

lVithout limiting myself to particularities except in such places asthey are definitely 'by' a cord, a skeleton loop-like lock-shoe withinthe frame, an a locking-dog for forcing the cord against the shoe.

3. In a pulley-block a frame, a sheave mounted therein, a skeleton,loop-like lockshoe secured within the frame, and an ogeeshapedlocklng-dog having at its lower end an eye through whlch an actuatingcord passes, one of its convex portions adapted to force said cordagainst said shoe.

4. In a pulley-block, a frame, a sheave mounted therein and adapted tobe traversed by a cord, a locking-dog pivoted in the frame, and askeleton lock-shoe one portion of which is adapted to be forced out ofnormal position when the locking dog is forced against the cord to forcethe latter against the shoe, the other portions of said shoe remainingin normal position.

5. In a pulley-block, a frame, a sheave mounted therein, a loop-likelock shoe arranged in the frame, and a locking-dog for forcing a cordagainst said shoe. I

6. In a pulley-block, a frame, a sheave mounted therein, a lock-shoeloosely but non-adjustably secured within the frame, alrlid means forforcing a cord against said s oe.

7. In a pulley-block, a frame, a lock-shoe held within the frame andmade of thin and relatively wide metal, such as strap iron, and alocking-dog for forcing a cord against said shoe.

8. In a pulley-block, a frame, a lock-shoe held loosely within the frameand made of thin and relatively wide metal, such as strap iron, and alocking-dog for forcing a cord against said shoe.

9. In a pulley-block, a frame, a sheave rotatable therein, rivetsarranged and held in the frame, a lock-shoe loosely and movably mountedon and surrounding said rivets, and a locking-dog adapted to force acord against said shoe.

H. W. WILKINSON, R. H. RICKLEFS. w

